1. Unplug the phone from the stereo and unlock the phone. Then plug it back in again. Repeat a few times...if that doesn't work....Push and hold the top button and home button of your phone for 10 - 15 seconds. Like taking a screen shot but longer. This will hard reset your iPhone.

2. If that doesn't work....Hard reset the stereo. Use the battery switch. Turn off the power for a few minutes. Then back on again.

3. If that doesn't work... Replace the white iPhone cable with one from Apple.